Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

350 Vortec stumbles on acceleration and “hangs”

Thread Tools
 
Search this Thread
 
Old 12-31-2023, 11:34 AM
  #1  
Junior Member
Thread Starter
 
92z23's Avatar
 
Join Date: Jul 2023
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Car: 1992 Iroc camaro
Engine: 305
Transmission: 5 speed
350 Vortec stumbles on acceleration and “hangs”

I’ve got a 92 RS Camaro with a 98 L31 vortec swapped in with a tuneport. Here recently, it’s had a hard start and has a stumble on throttle application and likes to “hang” when it revs down. It used to be real snappy and quick, but now it acts like it wants to fall on its face. I had 4 plug wires off the other day and mistakenly fired it up while they were off, I quickly shut it off and fixed the firing order, but since then it’s ran horrible. Would this be a possible timing issue? Or something else.
Old 12-31-2023, 11:36 AM
  #2  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 2,002
Received 145 Likes on 119 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 350 Vortec stumbles on acceleration and “hangs”

I mean, this may seem obvious but, did you put the wires back on in the right order?
Old 12-31-2023, 11:37 AM
  #3  
Junior Member
Thread Starter
 
92z23's Avatar
 
Join Date: Jul 2023
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Car: 1992 Iroc camaro
Engine: 305
Transmission: 5 speed
Re: 350 Vortec stumbles on acceleration and “hangs”

Originally Posted by aliceempire
I mean, this may seem obvious but, did you put the wires back on in the right order?
I did, double checked it today when I started it up.
Old 12-31-2023, 12:23 PM
  #4  
Supreme Member

 
ULTM8Z's Avatar
 
Join Date: Jan 2003
Posts: 4,036
Received 193 Likes on 167 Posts
Re: 350 Vortec stumbles on acceleration and “hangs”

Also probably need to think back carefully about everything you did. If it was running good before, something obviously changed.

Did you take out any of the plugs? Possibly cracked a ceramic body? Are the plug wires touching exhaust and maybe got damaged?

Example of something stupid... one time i pulled a plug out an accidentally dropped it. Ceramic looked ok but I didn't notice that the electrode gap nearly closed due to the way it evidently hit the ground. Didn't realize it until I put it back in and noted the misfire, prompting me to remove the plug again, at which point I found it.

Last edited by ULTM8Z; 12-31-2023 at 12:29 PM.
The following users liked this post:
Tom 400 CFI (12-31-2023)
Old 12-31-2023, 08:46 PM
  #5  
Junior Member
Thread Starter
 
92z23's Avatar
 
Join Date: Jul 2023
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Car: 1992 Iroc camaro
Engine: 305
Transmission: 5 speed
Re: 350 Vortec stumbles on acceleration and “hangs”

Originally Posted by ULTM8Z
Also probably need to think back carefully about everything you did. If it was running good before, something obviously changed.

Did you take out any of the plugs? Possibly cracked a ceramic body? Are the plug wires touching exhaust and maybe got damaged?

Example of something stupid... one time i pulled a plug out an accidentally dropped it. Ceramic looked ok but I didn't notice that the electrode gap nearly closed due to the way it evidently hit the ground. Didn't realize it until I put it back in and noted the misfire, prompting me to remove the plug again, at which point I found it.
none of the plugs were removed, just the ends from the cap were removed. I’ll check them tomorrow and check back.
Old 01-01-2024, 06:34 AM
  #6  
Supreme Member

iTrader: (8)
 
TTOP350's Avatar
 
Join Date: Oct 2001
Location: Il
Posts: 11,731
Received 775 Likes on 522 Posts
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 350 Vortec stumbles on acceleration and “hangs”


Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ecmagee1984
Engine Swap
1
12-23-2005 08:20 AM
1bad91Z
Aftermarket Product Review
22
06-03-2003 09:53 AM
steve8586iroc
TBI
9
04-29-2002 11:31 PM
3.8TransAM
NW Indiana and South Chicago Suburb
1
03-09-2002 01:19 AM



Quick Reply: 350 Vortec stumbles on acceleration and “hangs”



All times are GMT -5. The time now is 09:40 AM.